NCSN.MECH(5Q) Misc. Reference Manual Pages NCSN.MECH(5Q) NAME NCSN.MECH, ncsn.mech, calnet.mech - description of focal mechanism (fault plane solution) file format (Y2K compliant) DESCRIPTION FAULT PLANE SOLUTION FORMAT -------------------------- The format of the fault plane solutions produced by FPFIT are "Y2K" HYPO71 summary cards* in columns 1-82 augmented with the fault-plane solution parameters. The FORTRAN for- mats below are to be used for reading the fields. For more information see Reasenberg, P. A., and D. Oppenheimer, 1985, FPFIT, FPPLOT, and FPPAGE: Fortran computer programs for cal- culating and displaying earthquake fault-plane solu- tions, U.S. Geol. Surv. Open-File Rep. 85-739. * "Y2K" version is identical to original hypo71 format, except that the century occupies the first 2 columns Cols. Format Data _____ ______ ____ 1- 4 14 Year 5- 8 2I2, 1X month, day. 10- 13 2I2 Hour and minute. 14- 19 F6.2 Origin time seconds. 20- 22 F3.0 Latitude (deg). 23- 23 A1 S for south, blank or N for north 25- 28 F5.2 Latitude (min). 29- 32 F4.0 Longitude (deg). 33- 33 A1 E for east, blank otherwise. 34- 38 F5.2 Longitude (min). 39- 45 F7.2, 2X Depth (km). 48- 52 F5.2 Magnitude. See col. 80 for code 53- 55 I3 Number of P & S times with weights greater than 0.1. 56- 59 F4.0 Maximum azimuthal gap. 60- 64 F5.1 Distance to nearest station (km). 65- 69 F5.2 RMS travel time residual. 70- 74 F5.1 Horizontal error (km). 75- 79 F5.1, 2X Vertical error (km). 82- 82 A1, 1X If data source is Hypoinverse, then code designates type of magnitude posted in cols. 46- 50. L=ML based on above location, B=ML from UC Berkeley, C=coda, A=amplitude 84- 86 F3.0, 1X Dip direction (downdip azimuth in degrees,clockwise from north) 88- 89 F2.0 Dip angle in degrees down from horizontal 90- 93 F4.0, 2X Rake in degrees: 0=left lateral, 90=reverse, +-180=right lateral, - 90=normal 96- 99 F4.2, 1X Solution misfit value. 0=perfect fit, 1=perfect misfit (never exceeds 0.5 in reality). 101-103 I3, 1X Number of first motion observations used in solution SunOS 5.5.1 Last change: 1999/09/30 1 NCSN.MECH(5Q) Misc. Reference Manual Pages NCSN.MECH(5Q) 105-109 F5.2, 1X Solution misfit value + 90% confidence estimate. Useful for testing whether restricted solutions are within uncertainty region of free solution 111-114 F4.2, 1X Station distribution ratio (0-1). Lower numbers indicate data lie near nodal planes. 116-119 F4.2, 2X (# of machine picks)/(# of hand picks) 122-123 F2.0, 1X maximum half-width of 90% confidence range of strike 125-126 F2.0, 1X maximum half-width of 90% confidence range of dip 128-129 F2.0 maximum half-width of 90% confidence range of rake 130-130 A1 Convergence flag: C=no convergence; otherwise blank 131-131 A1 Multiple solution flag: *=multiple; otherwise blank 132-141 I10 Event ID # found in Hypoinverse archive file AUTHOR This document is maintained by David Oppenheimer (oppen@alum.wr.usgs.gov) Last revised: January 20, 1999 Modified for NCEDC by Doug Neuhauser, UC Berkeley Seismolog- ical Laboratory. SunOS 5.5.1 Last change: 1999/09/30 2